#include <stdio.h>
 
double factorial(unsigned int i)
{
	   if(i <= 1)
		      {
			            return 1;
				       }
	      return i * factorial(i - 1);
}
int  main()
{
	    int i = 5;
	        printf("%d 的阶乘为 %f\n", i, factorial(i));
		    return 0;
}
